reactor-netty client integration is too eager closing Response on error

If there is an error during 'extracting' the response, the current reactor-netty integration closes the response and rethrows the exception (code). This was done so that reactor-netty would not leak connections. However, the rethrown exception can contain the response (e.g. WebApplicationException) and that response's body is sometimes accessed in other places. Those places typically call `isClosed` before accessing the body, which is typically buffered.

I will soon submit a PR where we replace `close` with `releaseConnection`.